Internal-combustion engine.



0. A. & W. `OLSON. ,HFTRNAL CGMBUSTION ENGINE. "'APPLICAHON man MAY261916.

` Patented Feb. 19, 1918.

' o. A. a w.4 OLSON.

INTERNAL CUMBUSTION ENGINE. APPL-ICATION FILE@ H AY grglw Patented Feb.19,"19158. l

UNITED STATES PATENT oFFIoE.

oscAn n. oLsoN AND wAL'rni oLsoN,'o1il LEADER, MINNESOTA.

INTERNAL-COMBUSTION ENGINE.

specification of Letter Patent. Patented Feb. 19, 1918.

Application tiled May 26, 1916. Serial No. 100,965.

To all whom t may concern:

Be it known that we, Osoan A. OLSON and WALTER OLsoN, citizens ofthe United States,

residing at Leader, inthe county of Cass and State of Minnesota, have invented new and useful Improvements-in Internal-Combustion Engines, of which the following vis athereby giving a more'continuous t'orque to the crank shaft of the engine and producing a maximum amount of power with a. minimum amount of weight, also obtaining coinpactness and unusual strength for the entire structure.

. W ith the above and other objects in view, the invention consists in the novel construction, combination and arrangen'ient of parts, as herein described, illustrated and claimed.

In the accompanying drawings Figure 1 is a 'section taken diainetrically of the cylinder ofthe engine, showin the arrangement of the pistons therein an the relation of said pistons to the single crank shaft to which all of them are connected.

Fig. 2 is a similar View showing the pistons at the opposite ends of their throw.

Fig. 3 is al cross section on the line 8MS ot' Fig. 1.

Fig. 4 is a cross section on the line 4-4 of Fig. 1.

ln the engine illustrated in the accompanying` drawings we have shown aA single .cylinder 1 as that is all that is necessaryto an understanding of this invention, it .being obvious that as many cylinders may be elnployed as reqiired to give the desired power.

The crank shaft 2 has a single crank 3 to which is coupled a connecting rod@ .liar- ,ing a pivotal connection with the adjacent extremity of a iston rod-5 extending centrally and longitudinally within t-lie cylinder and operating through a stiilling box in the head thereof adjacent to the crank shaft 2. 'The piston rod 5 has fiXedly mounted thereon two I iisonsv 7 and 8 arranged in spaced relation cach other and movable toward and away from the heads 9 and 10 of the cylinder 1.

The crank shaft 2 is provided with other cranks 11 arranged at opposite sides of the crank 3 and4 referably offset one hundred and eighty shown in Figs. l and 2, each of the 'cranks egrees therefrom as clearly 11 having coupled thereto a connecting rod 12 which' is pivotally connected to a piston rod 13 Working through one of'a pair of stung' boxes 14 in the cylinder head 10.- The piston rods 13 operate in unison and carry at their free ends 'a third piston 15 which moves back and forth between the pistons 7 and 8. The piston 15 islxedly `mounted on both of the rods 13 andthe latter pass through openings in thepiiin 8 where they are surrounded by. packing rings 16`similar to those used in connection with the outer eriphery of a piston. The pis ton 15 1s a so formed with a central opening through which the piston rod -5 passes, .the

latter being surrounded by other packing rings 17 to prevent leaka. e;

At their outer ends t e piston rods l13 are supportedby cross heads 18 which move between cross head guides 19 shown as fastened to the cylinder head 10. The cylinder is provided with a central exhaust port 20 opened and closed by a mechanically operated and properly timed exhaust valve 21. Any suitable means may be employed for actuating and properly timing vthe exhaust valve 21. The cylinder is also provided with spark plugs 22 arranged adjacent to the inlet' ports 23 and 24. At its opposite ends and immediately adjacent to the cylinder heads 9 and 10;"-the latter is provided with ports 25 which communicate-with bypasses 26 leading to the inlet ports 23 and 24, the by-passes 26 being formed with internal valve seats 27 in conjunction with which operate spring closed check valves 28.

29 represents a carbureter'connected with an intake manifold the branches 30 of which `lead to opposite ends of the cylinder 1, the

the mixture admitted through the manifold 30 and past the check 11o valves 32 is drawn into the comi'iression chamber as the piston 7 moves inwardly toward the piston ,l5 and while the lutter heilig' driven outwardly during the explosion which takes place between said pis,

ton 15 and the piston 8. In the return or outward movement of the piston 7, the charge previously drawn into the chamber 33 is compressed and forced through the port 25 past the check valve 28 and through the by-pas's 26 into the combustion chamber 24 between the pistons 7 and 15. When the pistons 7 and 15 are at the nearest. point to each other as shown in Fig. 2, a spark is created by the plug 22 thereby exploding compressed mixture 'between the pistons and l5 and driving them in opposite directions'. The same operation applies with respect to the pistons l5 and 8. rlhe piston 8 drawing in the mixture as it moves inwardly and compressing the mixture as it moves toward the adjacent cylinder head, forcing the mixture through the respective by-pass 2G into the combustion chamber 25 between the pistons 8 and' 15.. These pistons as they move toward each other compress the charge and as they reach the nearest position to each other the charge is exploded by the adjacent plug.22 thus driving the pistons S und l5 in opposite directions. v It will thus be seen'that in each revolution of thecrank shaft 2, there are two explosions one of which drives the piston' 8 to- Ward the hea-d 10 of the cylinder and the .other of which drives the piston 7 toward the head 9 of the cylinder.

In View of the foregoing description, an exceedingly light, compact. and powerful engine -is employed, in which, While only one 'cylinder is used, there are two impulses in each complete revolution of the crank shaft. It will of course be understood that one, two or more of the power units hereinabove described may be eiiiplovcd in connection with a single crank shail according to the total. :ii'nount oi' power required lor any given purpose. These and other changes in the form, proportion and ininor details of construction may be resorted to without departing from the principle or sacriiieing any of the advarlages of the invention.

We claim:-

An internal combustion engine comprising a cylinder, heads closing both ends of said cylinder, a crank shaft, a piston rod extending centrally and lpngitlidinully oi.l said cylinder and uicratively coupled to said crank shaft, two pistons lixedly inount` ed on said piston rod in spared relation to each other and each operating entirely ut one side ot' :i central exhaust pori in the c vlind'er, an independently movable third piston interposed between said pistons and dividing the "cylinder so as lo forni two combustion chan'ibcrs and two compression chambers the outer walls of which are formed by the cylinder heads, the cylinder vbeing also provided with hy-passesallording communication between the said com` pression chambers and combustion chambers, und piston rods secured directly to said third piston through one of the first mentioned pistons and connected by rods directly to cranks of the crank shaft offset in relation to the crank to which the central piston rod is coupled.

In testimony whereof we aiiix our signav tures.

OSCAR A. OLSON. WALTER OLSON 

